RESUMO
The structure of the articular cartilage and disc of the temporomandibular jointin rats and monkey were studied with light,transmission and scanning electronmicroscopy.The articular cartilage covering the mandibular condyle is semilunar in shapeon cross section.Its thickest portion lies posterosuperiorly.The bony trabeculaesubjacent to the cartilage arrange vertically to the articular surface and concentrateto the thickest portion of the articular cartilage.The articular cartilage covering the mandibular fossa is similar to that on themandibular condyle,but contains fewer cartilage cells.Lacking a calcified areawith enlarged cartilage cells,the articular cartilage here may only be divided intothree areas.The articular disc consists of three areas:an upper,a middle,and a lowerone.The structure and ultrastructure of different parts of these cartilages with theirfunctions have been discussed.